The use of code division multiple access (CDMA) is being proposed for the next generation of cellular telecommunication networks. Additionally, code division multiple access is also being used in the IS-95 standard in the USA. CDMA is a direct sequence spread spectrum technique. In a wireless cellular network using CDMA, the mobile stations in one cell associated with a first base station will use the same frequency as mobile stations in an adjacent cell associated with the second base station. The different mobile stations can be distinguished by the respective base stations as each mobile station will be using a different spreading code.
Soft handover has been proposed in relation to CDMA systems. With soft handover, a mobile station is arranged to communicate with more than one base station at the same time. In particular, the same signals are sent to the mobile station from the various base stations and are combined in the mobile station. Likewise, the signals transmitted by the mobile station are received by the different base stations. The signals received by the different base stations are forwarded to a further network element which combines the signals received by the base stations. This is a cumbersome process in that the network element has to process the signals received from the base stations and also ensure that the signals are received by all the base stations for transmission to the mobile station. In more detail a major problem is the delay introduced by having an interface between the network element that processes the data and the base stations which receive the signals. In addition in some cases the required transmission capacity to convey these signals over the network between the base stations and the network element which processes the signals may cause problems.